Hydraulic transmission means



March 17, 1942. H. F. vossELER ETAI. 2,276,895

HYDRAULIC TRANSMISSION MEANS I Filed Nov. l5, 1959 Patented Mar. 17, 1942 HYDRAULIC TRANSMISSIQN MEANS- Heinrich Franz Vosseler and Harry Albertv WilliamV Pierard, Stratford, New-Zealand, assignorsl to saidsvosseler, said.. Pierard, William Henryr Young, Hawera,; New Zealand, and Bertram George Aiken Harkness, New Plymouth, New Zealand Application- November 13, 1939, SerialNo. 304,250 In- NewZealand November .118g 193$ Cl. 10S-11,),

3 Claims.

The invention relates to transmission means wherein a hydraulic fluid is employed to perform usefulr work', and has for its object, the provision of improved transmissiony means, designed to give ina comparatively-simple manner, increased flexibility over known forms of transmissions in the machine or apparatus operated by the fluid, combined with'ab-ility to reverse the action-thereof, and also-toutilize same to obtain a braking effect.

The improvedv means provided by the invention compriseafluidY circuit having incorporated therein, aL pluralityof pumping units of different output capacities, andeach of which is adapted to-operate continuously at full output; and a ilow controll valve and an exhaust control valve formed andcapable of being operated to enable the full output of all of the pumping units to be utilizedv to perform work or to be diverted without performing work, or for any portion of said output to be utilized to perform work and the remainder to be diverted without performing work.

Thepumping units can comprise gear or cog wheel pumps, and the control valves can be of the open ended hollow" barrel type containing radial ports and'` operable in bodies containing radial ports, said barrels beingcoupled or geared together to operate in unison.

In the-accompanying drawing, in conjunction with which the invention will be more particularlyy described,

Figure 1 illustrates diagrammatically, the general arrangement of the meansemployed,

Figure 2 illustrates a modification,

Figure 3 is a vertical'sectional View of one of the control valves employed, and

Figure 4 is a sectional plan view on the line 4-4, Figure 3, while Figures 5'and 6 illustrate the arrangements of the ports in the barrels of the iloW control valve andthe exhaust control valve, respectively;

In. carryingY out the invention hydraulic fluid is drawn from a tank or reservoir I and placed under: pressure by pumps of different capacities, either. built and driven separately or combined so as to be capable. of being driven as a single apparatus having units of different capacities, any form of pump suitable for the purpose being utilized.

A convenient form of pump can comprise a gear or cog wheel pump having incorporated thereinseparate pumping units. of different capacites,l and all driven together from and by the. same motor or. powerv unit oper-atedl shaft 2.

Thus a gear or cog wheel pump suitablefor the purpose ofthe invention can comprise three pumping units, 3, 4, 5, unit 4 having twice the capacity of unit 3, while unit 5 has twice the capacity of' unit 4 and four times the capacity of unit 3,1 said' units 3, 4, 5 or pumps, if separate pumpsare used, having inlets E, 1, 8 respectively in communication through a pipe 2| with the fluid tank or` reservoir I, and outlets 9, Ii), I-I respectively, in communication through pipes 23, 24;, 25; with geared together ow control, andexhaust control valves I2 and I3.

The flow and the exhaust control valves I2* and lf3 each comprises a hollow barrel I4 open at the bottom, (Figures 3 and 4) rotatable in a body I5 containing ports I6, I-l, I8 adapted to be connected with the delivery sides of the pumping units, or pumps 3, 4; 5, the interior of the exhaust'control valve I3 also being in communicationV through-thelower endv of its barrel I4, pipes I9, 2li", tank or reservoir'l and pipe 2I^,vwith` the intakes 6, 'I, 8 of the pumping units or pumps 3, 4, 5 while the interior of the flow control valve I2 is also in communication through the lower end of its barrel I4 and thepipe 22 with the machine or apparatus to be operated, the valveV barrels I4* having formed therein radial ports (Figures5 and 6-) capable of being made to register with the ports I6, I'I, I8- in the bodies I5 in communication with the delivery sides of the pumping units or pumps 3, 4, 5. I

The connecting pipes 23, 24, 25 between the delivery sides 9, I0, II of the pumping units or pumpsA 3*-, 4'and5 andthe control valves I2, I3 are branched so as to communicatewith eachof the latter, the branches 230 24aand 25a1eading to the exhaust control valve I3, and the ports .in the'valve barrels I4 are formed and arranged so that when'the flow control valve I2 is open to the delivery side of' a particular pumping unit or pump 3, 4'- or 5, the exhaust valve I3 is closed to that pumping unit or pump 3, 4 or 5, whereby fluid put under pressure by the selected unit or pump is passed all through the flow control valve I2 to the machine or apparatus it is intended to operate, and from which it passes via the return pipe or' connection 20 to the tank or reservoir I for re-use.

Each pumping unit or pump 3, 4, 5, delivers or discharges uid at' its full capacity continuously, and the ports in the barrel I4 of the exhaust control valve I3 are arranged in relation to the` ports in the barrel I4 of the flow control valve I2, so that when any combination of'ports inthe barrel I4 or the flow control valve I l2is open'- through the ports I6, I'I, I8 of said valve to the discharge sides 9, I0, I I of the piunping units or pumps 3, 4, 5, and the latter are passing fluid through the connections 23, 24, 25 to and through the ow control valve I2, fluid in excess of that passed under pressure to and through the flow control valve I2, is diverted through such of the branches 23a, 24a, 25a of said connections 23, 24, 25, as are open to the exhaust control valve I3, to and through the latter to pass into the exhaust or return pipe 20 from the machine or apparatus being operated, and be returned to the tank or reservoir I, for re-use, the diverted fluid owing to it not taking any of the load only being under such pressure as is necessary to cause same to circulate.

The ports in the barrels I4 of the valves I2, I3 are of different sizes in accordance with the capacities of the pumping units or pumps 3, 4, 5 they serve, ports adapted to be put in communication with the pumping unit or pump of the smallest capacity being smaller than the other ports, while ports adapted to be put in communication with or to serve the pumping unit or pump of greatest capacity being larger than the other ports, while intermediate sized ports for serving pumping units or pumps having capacities between the units or pumps of smallest and greatest capacities, are also provided in the barrels.

By arranging the different sized ports in the valve barrels I4, in varying combinations, and by providing that excess (if any) of fluid over that capable of being passed by a selected combination of ports in the ilow control valve I2, is by-passed via the exhaust control valve I3 to the return pipe 20 to the fluid tank or reservoir I, the pumping units or pumps 3, 4, 5 are all enabled to be run continuously at full capacity, while the transmission of fluid to perform work can be varied considerably, and merely by the operation of the control valves I2, I3, to obtain a desired result in the operation of the machine or apparatus, within the limits of said control valves.

Explaining further the operation of the control valves I2, I3, and referring to Figures 5 and 6 which represent the barrels I4 of the flow control valve I2 (Figure 5) and the exhaust control valve I3 (Figure 6), opened out, the bodies I5 of said valves I2, I3 contain identical ports I6, I1 and I8, arranged in vertical rows, the smaHest ports I6 serving the pumping unit or pump 3 of smallest capacity, the intermediate size ports I'I serving the intermediate pumping unit or pump 4, while the largest ports I8 serve the pumping unit or pump 5 of greatest capacity.

Each barrel I4 has formed therein, a horizontal row of ports, any one of which will fully open the port I5 in the body I5 in which it works, also a horizontal row of ports any one of which will fully open the port I'I in the body I5 in which it works, and a further horizontal row of ports, any one of which will fully open the port I8 in the body I5 in which it works.

The ports in the barrels I4 are also arranged in vertical rows, A, B, C, D, E, F, G, and said barrels I4 are coupled or geared together as at 33 (Figure l), so that when the vertical row A of ports in the barrel I4 of the pressure control valve I2 (Figure 5) is presented to ports I 6, I'I and I8 of said valve to fully open same, the blank portion of the barrel I4 of the exhaust control'valve I3 (Figure 6) is presented to the ports I6, II, I8 thereof and fully closes the said valve I3, whereby the total fluid output of the pumping units or pumps 3, 4, 5, is passed to the pipe 22 and utilized, there being no exhaust via the valve I3.

If however, the vertical row B of ports in the barrel I4 of the valve I2 (Figure 5) is presented to the ports I6, I'I and I8 thereof, it will be seen that only the outputs of pumping units or pumps v 4 and 5 are allowed to pass via valve I4 to the pipe 22, the output of unit or pump 3 being diverted Via branch 23a to pass via the port in row G of barrel I4 (Figure 6) of the exhaust control valve I3 through the latter and pipes I9, 20 to the tank or reservoir I.

A two way valve 26 inserted in the fluid delivery pipe 22 from the pressure control valve I2 to the machine or apparatus being operated, and also in the fluid return or exhaust pipe 20 from the latter, can be operated to reverse the functions of the inlet and the exhaust ports of the machine or apparatus, and so provide for reverse operation thereof.

Also by providing a shut off cock or Valve 2l in the fluid return pipe 2U to the tank or reservoir I, the flow of fluid to the latter from the machine or apparatus can be controlled or regulated to give a braking action or effect on or to said machine or apparatus.

A relief valve 28 suitably loaded can be' provided in the fluid return pipe 20 to the tank or reservoir I, and also the iluid supply connections 23, 24, 25 between the pumping units or pumps 3, 4, 5, and the control valves I2 and I3, can be provided with relief valves 29, 3, 3l which are connected by pipes 29a, 36a, 3Ia with the iluid tank or reservoir I, while the relief valve 28 in the fluid return pipe 20 aforesaid, is tted with a by-pass 32 to beyond the shut off cock 2'I in said return pipe.

As illustrated in Figure 2, instead of fluid from the valve I3 also fluid exhausted from the machine or apparatus ybeing operated, passing through the tank or reservoir I, and the pumping units or pumps 3, 4 and 5 drawing their supply from the latter, the pipe 20 can `be connected directly with the intakes 6, 'I and 8 of the pumping units or pumps 3, 4 and 5, thereby providing practicallyl an enclosed circuit, and in this case the tank'or reservoir I would be connected by a connection 34 containing a check or non-return valve 35, allowing fluid to enter, but not to leave the circuit, while excess pressure due to heat expansion or other causes can be allowed to escape back into the tank or reservoir I via a spring loaded relief valve 36 on a bypass 31. y

The transmission means herein described are particularly adapted for use with engines of the rotary type, although they can quite well be used with engines of the reciprocating type.

What we do claim and desire to obtain by Letters Patent of the United States of America is:

l. Hydraulic transmission means including a reservoir in combination with a iluid circuit, a series of pumping units communicating with said reservoir and each succeeding unit having twice the output capacity of the preceding unit and all of said units being adapted to operate at continuously full lcapacity to draw iluid from said reservoir, branched discharge pipes extending from each unit, each succeeding discharge pipe having twice the size of the preceding pipe to conform to the output capacity of its corresponding pumping unit, flow control valve means arranged at one branched end oflsaiddischarge pipes Vand exhaust'control Valve means varranged at the other branched end of said discharge pipes, said valve means adapted to operate in unison whereby the pumping units may be regulated so that the full capacity is utilized for Work or diverted back to said reservoir, or so that any portion of the output can be utilized for work and the remainder diverted back to the reservoir Without performing work.

2. Hydraulic transmission means as claimed in claim l, in which the control valve means includes body members having a plurality of inlet ports in communication with and having the same capacity as the discharge pipes, and rotatable hollow barrels arranged within the body members, open at their lower ends, and having a plurality of radial ports of the same size as the inlet ports of the body members.

3. Hydraulic transmission means as claimed in claim 1, in which the flow control valve means and the exhaust control valve means each includes a hollow body having a plurality of inlet ports communicating with and of the same capacity as the discharge pipes, a rotatable hollow barrel arranged within each body member, open at its lower end and having a plurality of radial ports of the same size as the inlet ports of the body member, the radial ports of the hollow barrel of the flow control valve means being placed in an opposite arrangement to the radial ports of the hollow barrel ofthe exhaust valve control means whereby an output regulation is obtained which varies from complete pressure output to a complete exhaust output with intermediate arrangements of any portion of the output being utilized for pressure and the remainder diverted through the exhaust.

HEINRICH FRANZ VOSSELER.

HARRY ALBERT WILLIAM PIERARD. 

